count the number of occurrences of each character in a string in java code example

Example 1: count occurrences of character in string java 8

String someString = "elephant";
long count = someString.chars().filter(ch -> ch == 'e').count();
assertEquals(2, count);
 
long count2 = someString.codePoints().filter(ch -> ch == 'e').count();
assertEquals(2, count2);

Example 2: find number of occurrences of a substring in a string java

public static int count(String str, String target) {
    return (str.length() - str.replace(target, "").length()) / target.length();
}